The invention relates to a device for the preparation of plastics material for recycling purposes, in particular thermoplastic plastics material, comprising a container into which the material to be processed is fed from above through an inlet opening, and at least one mixing and/or comminuting tool arranged in the container and rotating about the vertical axis of the container, wherein the material treated by this tool is fed through an outlet opening which is arranged at the bottom of the container and to which the feed opening of a housing of at least one screw is fluidly connected, the housing being connected, preferably tangentially, to the container, and wherein that side wall of the feed opening at which the tool discharges, seen in section, defines a widening of the feed opening, the widening extending continuously towards the axis of the housing of the screw.
Devices of this type are known, e.g. AT 407 972 B. They usually have an extruder screw which feeds the material conveyed by it directly to the following processing stage, usually a granulator. However, the screw can also be a simple conveyor screw which feeds the material to a following processing step, e.g. further processing by means of rotating tools. Only after this processing step is the material fed to a plasticizer or agglomerator. Essentially, the known devices operate satisfactorily, but frequently have difficulties when charging the apparatus connected to the outlet opening, in particular when this apparatus is a plasticizer or agglornerator. The infeed to the screw should be as uniform as possible and the delivery from this apparatus should also be as uniform as possible, which is of particular importance when a molding plant is connected to an extruder. In the case of a molding plant, it is important that the material to be molded is supplied as uniformly as possible. The aforementioned difficulties are caused, among other things, by the fact that the material to be processed usually varies greatly, both with respect to the chemical composition of the material and with respect to its external constitution (degree of soiling, particle size, particle shape, etc.).